diff --git a/benchmarks/benchjs/casting.js b/benchmarks/benchjs/casting.js
index d5ca05d0141..1b9b3dbeb91 100644
--- a/benchmarks/benchjs/casting.js
+++ b/benchmarks/benchjs/casting.js
@@ -136,6 +136,6 @@ suite.add('Casting - Embedded Docs - 0 Docs', {
       out.ops = item.hz;
       outObj[item.name.replace(/\s/g, '')] = out;
     });
-    console.log(JSON.stringify(outObj));
+    console.dir(outObj, {depth: null, colors: true});
   }
 }).run({async: true});
diff --git a/benchmarks/benchjs/delete.js b/benchmarks/benchjs/delete.js
index 028ac6b34e7..3791ad3a5ad 100644
--- a/benchmarks/benchjs/delete.js
+++ b/benchmarks/benchjs/delete.js
@@ -61,7 +61,7 @@ mongoose.connect('mongodb://localhost/mongoose-bench', function(err) {
       nData.likes = data.likes;
       nData.address = data.address;
       user.insert(nData, function(err, res) {
-        dIds.push(res[0]._id);
+        dIds.push(res.insertedIds[0]);
         --count || next();
       });
     }
@@ -120,7 +120,7 @@ mongoose.connect('mongodb://localhost/mongoose-bench', function(err) {
           out.ops = item.hz;
           outObj[item.name.replace(/\s/g, '')] = out;
         });
-        console.log(JSON.stringify(outObj));
+        console.dir(outObj, {depth: null, colors: true});
       }
     });
     function next() {
diff --git a/benchmarks/benchjs/insert.js b/benchmarks/benchjs/insert.js
index b2d257880b0..a8c15117304 100644
--- a/benchmarks/benchjs/insert.js
+++ b/benchmarks/benchjs/insert.js
@@ -169,7 +169,7 @@ mongoose.connect('mongodb://localhost/mongoose-bench', function(err) {
           out.ops = item.hz;
           outObj[item.name.replace(/\s/g, '')] = out;
         });
-        console.log(JSON.stringify(outObj));
+        console.dir(outObj, {depth: null, colors: true});
       }
     }).run({async: true});
   });
diff --git a/benchmarks/benchjs/multiop.js b/benchmarks/benchjs/multiop.js
index 8b121a19391..79fc73d38f7 100644
--- a/benchmarks/benchjs/multiop.js
+++ b/benchmarks/benchjs/multiop.js
@@ -126,7 +126,7 @@ mongoose.connect('mongodb://localhost/mongoose-bench', function(err) {
         if (err) {
           throw err;
         }
-        dIds.push(res[0]._id);
+        dIds.push(res.insertedIds[0]);
         --count || next();
       });
       BlogPost.create(blogData, function(err, bp) {
@@ -142,7 +142,7 @@ mongoose.connect('mongodb://localhost/mongoose-bench', function(err) {
         if (err) {
           throw err;
         }
-        bdIds.push(res[0]._id);
+        bdIds.push(res.insertedIds[0]);
         --count || next();
       });
     }
@@ -447,7 +447,7 @@ mongoose.connect('mongodb://localhost/mongoose-bench', function(err) {
           out.ops = item.hz;
           outObj[item.name.replace(/\s/g, '')] = out;
         });
-        console.log(JSON.stringify(outObj));
+        console.dir(outObj, {depth: null, colors: true});
       }
     });
     function next() {
diff --git a/benchmarks/benchjs/population.js b/benchmarks/benchjs/population.js
index d7b7cb7608b..5942c8ac9f1 100644
--- a/benchmarks/benchjs/population.js
+++ b/benchmarks/benchjs/population.js
@@ -387,7 +387,7 @@ mongoose.connect('mongodb://localhost/mongoose-bench-pop', function(err) {
         out.ops = item.hz;
         outObj[item.name.replace(/\s/g, '')] = out;
       });
-      console.log(JSON.stringify(outObj));
+      console.dir(outObj, {depth: null, colors: true});
     }
   });
   function next() {
diff --git a/benchmarks/benchjs/update.js b/benchmarks/benchjs/update.js
index 62bd971226b..3c32a9b20ef 100644
--- a/benchmarks/benchjs/update.js
+++ b/benchmarks/benchjs/update.js
@@ -115,7 +115,7 @@ mongoose.connect('mongodb://localhost/mongoose-bench', function(err) {
       });
       var nData = utils.clone(data);
       user.insert(nData, function(err, res) {
-        dIds.push(res[0]._id);
+        dIds.push(res.insertedIds[0]);
         --count || next();
       });
       BlogPost.create(blogData, function(err, bp) {
@@ -132,7 +132,7 @@ mongoose.connect('mongodb://localhost/mongoose-bench', function(err) {
         if (err) {
           throw err;
         }
-        bdIds.push(res[0]._id);
+        bdIds.push(res.insertedIds[0]);
         --count || next();
       });
     }
@@ -329,7 +329,7 @@ mongoose.connect('mongodb://localhost/mongoose-bench', function(err) {
           out.ops = item.hz;
           outObj[item.name.replace(/\s/g, '')] = out;
         });
-        console.log(JSON.stringify(outObj));
+        console.dir(outObj, {depth: null, colors: true});
       }
     });
     function next() {